Update libwebp to 1.0.3

5 files changed, 36 insertions, 22 deletions

diff --git a/thirdparty/libwebp/src/enc/backward_references_enc.c b/thirdparty/libwebp/src/enc/backward_references_enc.c
index 3ab7b0ac7d..d445b40fc5 100644
--- a/thirdparty/libwebp/src/enc/backward_references_enc.c
+++ b/thirdparty/libwebp/src/enc/backward_references_enc.c
@@ -191,13 +191,14 @@ void VP8LHashChainClear(VP8LHashChain* const p) {
 
 // -----------------------------------------------------------------------------
 
-#define HASH_MULTIPLIER_HI (0xc6a4a793ULL)
-#define HASH_MULTIPLIER_LO (0x5bd1e996ULL)
+static const uint32_t kHashMultiplierHi = 0xc6a4a793u;
+static const uint32_t kHashMultiplierLo = 0x5bd1e996u;
 
-static WEBP_INLINE uint32_t GetPixPairHash64(const uint32_t* const argb) {
+static WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW WEBP_INLINE
+uint32_t GetPixPairHash64(const uint32_t* const argb) {
   uint32_t key;
-  key  = (argb[1] * HASH_MULTIPLIER_HI) & 0xffffffffu;
-  key += (argb[0] * HASH_MULTIPLIER_LO) & 0xffffffffu;
+  key  = argb[1] * kHashMultiplierHi;
+  key += argb[0] * kHashMultiplierLo;
   key = key >> (32 - HASH_BITS);
   return key;
 }
diff --git a/thirdparty/libwebp/src/enc/histogram_enc.c b/thirdparty/libwebp/src/enc/histogram_enc.c
index 8ac6fa8e02..d89b98524a 100644
--- a/thirdparty/libwebp/src/enc/histogram_enc.c
+++ b/thirdparty/libwebp/src/enc/histogram_enc.c
@@ -929,9 +929,8 @@ static int HistogramCombineStochastic(VP8LHistogramSet* const image_histo,
   }
 
   mappings = (int*) WebPSafeMalloc(*num_used, sizeof(*mappings));
-  if (mappings == NULL || !HistoQueueInit(&histo_queue, kHistoQueueSize)) {
-    goto End;
-  }
+  if (mappings == NULL) return 0;
+  if (!HistoQueueInit(&histo_queue, kHistoQueueSize)) goto End;
   // Fill the initial mapping.
   for (j = 0, iter = 0; iter < image_histo->size; ++iter) {
     if (histograms[iter] == NULL) continue;
diff --git a/thirdparty/libwebp/src/enc/predictor_enc.c b/thirdparty/libwebp/src/enc/predictor_enc.c
index 802e89693e..2e6762ea0d 100644
--- a/thirdparty/libwebp/src/enc/predictor_enc.c
+++ b/thirdparty/libwebp/src/enc/predictor_enc.c
@@ -202,7 +202,7 @@ static uint32_t NearLossless(uint32_t value, uint32_t predict,
   }
   if ((value >> 24) == 0 || (value >> 24) == 0xff) {
     // Preserve transparency of fully transparent or fully opaque pixels.
-    a = NearLosslessDiff(value >> 24, predict >> 24);
+    a = NearLosslessDiff((value >> 24) & 0xff, (predict >> 24) & 0xff);
   } else {
     a = NearLosslessComponent(value >> 24, predict >> 24, 0xff, quantization);
   }
@@ -215,12 +215,12 @@ static uint32_t NearLossless(uint32_t value, uint32_t predict,
     // The amount by which green has been adjusted during quantization. It is
     // subtracted from red and blue for compensation, to avoid accumulating two
     // quantization errors in them.
-    green_diff = NearLosslessDiff(new_green, value >> 8);
+    green_diff = NearLosslessDiff(new_green, (value >> 8) & 0xff);
   }
-  r = NearLosslessComponent(NearLosslessDiff(value >> 16, green_diff),
+  r = NearLosslessComponent(NearLosslessDiff((value >> 16) & 0xff, green_diff),
                             (predict >> 16) & 0xff, 0xff - new_green,
                             quantization);
-  b = NearLosslessComponent(NearLosslessDiff(value, green_diff),
+  b = NearLosslessComponent(NearLosslessDiff(value & 0xff, green_diff),
                             predict & 0xff, 0xff - new_green, quantization);
   return ((uint32_t)a << 24) | ((uint32_t)r << 16) | ((uint32_t)g << 8) | b;
 }
@@ -587,7 +587,7 @@ static void GetBestGreenToRed(
       }
     }
   }
-  best_tx->green_to_red_ = green_to_red_best;
+  best_tx->green_to_red_ = (green_to_red_best & 0xff);
 }
 
 static float GetPredictionCostCrossColorBlue(
@@ -666,8 +666,8 @@ static void GetBestGreenRedToBlue(
       break;  // out of iter-loop.
     }
   }
-  best_tx->green_to_blue_ = green_to_blue_best;
-  best_tx->red_to_blue_ = red_to_blue_best;
+  best_tx->green_to_blue_ = green_to_blue_best & 0xff;
+  best_tx->red_to_blue_ = red_to_blue_best & 0xff;
 }
 #undef kGreenRedToBlueMaxIters
 #undef kGreenRedToBlueNumAxis
diff --git a/thirdparty/libwebp/src/enc/quant_enc.c b/thirdparty/libwebp/src/enc/quant_enc.c
index 03c682e3ae..01eb565c7f 100644
--- a/thirdparty/libwebp/src/enc/quant_enc.c
+++ b/thirdparty/libwebp/src/enc/quant_enc.c
@@ -33,7 +33,7 @@
 
 // number of non-zero coeffs below which we consider the block very flat
 // (and apply a penalty to complex predictions)
-#define FLATNESS_LIMIT_I16 10      // I16 mode
+#define FLATNESS_LIMIT_I16 0       // I16 mode (special case)
 #define FLATNESS_LIMIT_I4  3       // I4 mode
 #define FLATNESS_LIMIT_UV  2       // UV mode
 #define FLATNESS_PENALTY   140     // roughly ~1bit per block
@@ -988,6 +988,7 @@ static void PickBestIntra16(VP8EncIterator* const it, VP8ModeScore* rd) {
   VP8ModeScore* rd_cur = &rd_tmp;
   VP8ModeScore* rd_best = rd;
   int mode;
+  int is_flat = IsFlatSource16(it->yuv_in_ + Y_OFF_ENC);
 
   rd->mode_i16 = -1;
   for (mode = 0; mode < NUM_PRED_MODES; ++mode) {
@@ -1003,10 +1004,14 @@ static void PickBestIntra16(VP8EncIterator* const it, VP8ModeScore* rd) {
         tlambda ? MULT_8B(tlambda, VP8TDisto16x16(src, tmp_dst, kWeightY)) : 0;
     rd_cur->H = VP8FixedCostsI16[mode];
     rd_cur->R = VP8GetCostLuma16(it, rd_cur);
-    if (mode > 0 &&
-        IsFlat(rd_cur->y_ac_levels[0], kNumBlocks, FLATNESS_LIMIT_I16)) {
-      // penalty to avoid flat area to be mispredicted by complex mode
-      rd_cur->R += FLATNESS_PENALTY * kNumBlocks;
+    if (is_flat) {
+      // refine the first impression (which was in pixel space)
+      is_flat = IsFlat(rd_cur->y_ac_levels[0], kNumBlocks, FLATNESS_LIMIT_I16);
+      if (is_flat) {
+        // Block is very flat. We put emphasis on the distortion being very low!
+        rd_cur->D *= 2;
+        rd_cur->SD *= 2;
+      }
     }
 
     // Since we always examine Intra16 first, we can overwrite *rd directly.
@@ -1087,7 +1092,8 @@ static int PickBestIntra4(VP8EncIterator* const it, VP8ModeScore* const rd) {
                   : 0;
       rd_tmp.H = mode_costs[mode];
 
-      // Add flatness penalty
+      // Add flatness penalty, to avoid flat area to be mispredicted
+      // by a complex mode.
       if (mode > 0 && IsFlat(tmp_levels, kNumBlocks, FLATNESS_LIMIT_I4)) {
         rd_tmp.R = FLATNESS_PENALTY * kNumBlocks;
       } else {
@@ -1242,11 +1248,19 @@ static void RefineUsingDistortion(VP8EncIterator* const it,
       if (mode > 0 && VP8FixedCostsI16[mode] > bit_limit) {
         continue;
       }
+
       if (score < best_score) {
         best_mode = mode;
         best_score = score;
       }
     }
+    if (it->x_ == 0 || it->y_ == 0) {
+      // avoid starting a checkerboard resonance from the border. See bug #432.
+      if (IsFlatSource16(src)) {
+        best_mode = (it->x_ == 0) ? 0 : 2;
+        try_both_modes = 0;  // stick to i16
+      }
+    }
     VP8SetIntra16Mode(it, best_mode);
     // we'll reconstruct later, if i16 mode actually gets selected
   }
diff --git a/thirdparty/libwebp/src/enc/vp8i_enc.h b/thirdparty/libwebp/src/enc/vp8i_enc.h
index 3a1967da88..24e1944610 100644
--- a/thirdparty/libwebp/src/enc/vp8i_enc.h
+++ b/thirdparty/libwebp/src/enc/vp8i_enc.h
@@ -32,7 +32,7 @@ extern "C" {
 // version numbers
 #define ENC_MAJ_VERSION 1
 #define ENC_MIN_VERSION 0
-#define ENC_REV_VERSION 2
+#define ENC_REV_VERSION 3
 
 enum { MAX_LF_LEVELS = 64,       // Maximum loop filter level
        MAX_VARIABLE_LEVEL = 67,  // last (inclusive) level with variable cost